The invention provides an 
anomaly detection method based on a cumulative sum 
control chart and applied to a 
satellite power supply 
system, relates to the field of power supply 
system fault diagnosis, and aims to solve the problems that a threshold value is wider, small faults cannot be detected and warned early and the like for conventional 
anomaly detection of the 
satellite power supply 
system. The method comprises the following steps: historical data of normal operation of an NI-MH battery type 
satellite power supply in a time period is acquired, and the 
hydrogen pressure value of the power supply is selected as an evaluation parameter; the 
hydrogen pressure value is divided into m groups, and the average value pj of each group of 
hydrogen pressure values is calculated; the statistical properties of the 
hydrogen pressure values of the power supply are calculated, and the allowed deviator and the threshold value of the cumulative sum 
control chart are determined; the average value pi of 
hydrogen pressure values of a to-be-detected satellite power supply is calculated; the average value pi of the 
hydrogen pressure values is taken as input of a cumulative sum function, and an output value is drawn in the cumulative sum 
control chart; whether the cumulative sums S+(i) and S-(i) corresponding to the hydrogen pressure values of the to-be-detected satellite power supply exceed the threshold value of the cumulative sum control chart is judged, and the current working state of the power supply system is judged. The method is applicable to the field of fault diagnosis for an NI-MH battery type satellite power supply system.